DESCRIPTION:(provided by applicant) The purpose of this study is to characterize the neural mechanisms of figure-ground organizations in the high level visual cortex of the monkey. Figure-ground organization is a critical stage of visual processing, in which the visual system determines both what objects are present in the visual scence and the depth relations among those objects. Understanding how perceptual organization is instantiated at the neural level will provide clues into how normal vision breaks down in neuropsychological disorders such as apperceptive agnosia. In this study, we will determine whether neurons in inferotemporal cortex (area TE) represent preferentially those scene elements which posses the status of figure as opposed to ground. To address this issue, we will train macaque monkeys to provide a behavioral report of what component in a figure-ground display appears to stand out as foreground. We will then determine the extent to which neurons in TE are sensitive to the figure-ground status of those components, and the extent to which the monkey's behavior corresponds to the selectivity of TE neurons. The results of these studies will elucidate the role of high level visual cortex in establishing the perceptual organization of the visual world, and thus provide insight into processes of visual perception that are disrupted following temporal lobe injury.